Surface water

The Taunton River and its complex network of tributaries drain about 530 mi2 of southeastern Massachusetts. The relatively low relief of land in the basin has resulted in low stream gradients and many wetlands. The basin contains at least 50 mi2 of wetlands and a total of 219 lakes and ponds, 135 of which have an area of 10 acres or more. Five of the lakes cover more than 500 acres: Assawompset Pond in Lakeville (2,024 acres), Long Pond in Lakeville and Freetown (1,721 acres), Great Quittacas Pond in Lakeville (1,185 acres), Norton Reservoir in Norton (529 acres), and Monponsett Pond in Halifax and Hanson (528 acres).

The Taunton River begins at the confluence of the Matfield and Town Rivers just east of Bridgewater and flows about 36 mi in a generally southward direction through Taunton to Mount Hope Bay, a part of Narragansett Bay at Fall River. The lower 8 or 9 mi of the river is a tidal estuary, above which the river is affected by tides for about 15 mi.